From: Michal Simek <monstr@monstr.eu>
To: Mike Frysinger <vapier.adi@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
rostedt@goodmis.org, linux-kernel@vger.kernel.org,
tglx@linutronix.de, mingo@elte.hu, linux-arch@vger.kernel.org
Subject: Re: [PATCH] asm-generic: Use raw_local_irq_save/restore instead local_irq_save/restore
Date: Wed, 28 Jul 2010 07:23:40 +0200 [thread overview]
Message-ID: <4C4FBEDC.4000008@monstr.eu> (raw)
In-Reply-To: <AANLkTim3Po8XD3UFB-h6UH4HWtSZP9MA+V63TE5tQgku@mail.gmail.com>
Mike Frysinger wrote:
> On Tue, Jul 27, 2010 at 19:18, Andrew Morton wrote:
>> On Mon, 26 Jul 2010 10:49:50 +0200 Michal Simek wrote:
>>> start/stop_critical_timing function for preemptirqsoff, preemptoff
>>> and irqsoff tracers contains atomic_inc and atomic_dec operations.
>>>
>>> Atomic operations used local_irq_save/restore macros to ensure
>>> atomic access but they are traced by the same function which is causing
>>> recursion problem.
>>>
>>> The reason is when these tracers are turn ON then local_irq_save/restore
>>> macros are changed in include/linux/irqflags.h to call trace_hardirqs_on/off
>>> which call start/stop_critical_timing.
>>>
>>> Microblaze was affected because use generic atomic implementation.
>> Seems that this will also affect blackfin, mn10300 and score. I guess
>> they aren't supporting tracing yet?
>
> do you mean TRACE_IRQFLAGS_SUPPORT ? Blackfin should ... my
> understanding was that arches just needed to implement asm/irqflags.h
> for it.
Blackin uses own include/asm/atomic.h implementation where shouldn't be
a problem with irqflags tracer. Look at my second post.
Michal
--
Michal Simek, Ing. (M.Eng)
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/
Microblaze U-BOOT custodian
next prev parent reply other threads:[~2010-07-28 5:27 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1274863724-14906-1-git-send-email-monstr@monstr.eu>
[not found] ` <1274863724-14906-2-git-send-email-monstr@monstr.eu>
2010-05-26 14:42 ` [PATCH] asm-generic: Use raw_local_irq_save/restore instead local_irq_save/restore Steven Rostedt
2010-05-26 17:08 ` Andrew Morton
2010-05-26 17:11 ` Steven Rostedt
2010-05-27 7:14 ` Michal Simek
2010-05-27 9:11 ` Yong Zhang
2010-07-26 8:49 ` Michal Simek
2010-07-27 23:18 ` Andrew Morton
2010-07-27 23:54 ` Mike Frysinger
2010-07-28 5:23 ` Michal Simek [this message]
2010-07-28 5:20 ` Michal Simek
2010-07-28 5:35 ` Mike Frysinger
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4C4FBEDC.4000008@monstr.eu \
--to=monstr@monstr.eu \
--cc=akpm@linux-foundation.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
--cc=vapier.adi@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox